Fate. This 4 - letter word often appears in fictional works. It can be used to drive the plot, such as when characters are trying to defy their fate or come to terms with it. For example, in Greek mythology - based fictions, many heroes struggle with their pre - determined fates.
Lies. In many detective or mystery fictions, lies are often a crucial part of the plot. Characters may tell lies to cover up their secrets or mislead others.
The word 'nod' could also be considered in a way related to a novel. When reading a novel, we might nod in understanding or approval at certain points in the story. It's a bit of a stretch but still a 3 - letter word.